A radio frequency identification (RFID) system may identify a thin flat-shaped tag adhered to an object, that is, an RFID tag, without touching it by use of a frequency signal, and process information about the object.
In a conventional passive RFID system, an RFID tag is provided with a power from a frequency signal of an RFID reading apparatus. The RFID tag uses an antenna and a rectifier to rectify a carrier frequency through the antenna to a direct current voltage to operate a digital circuit of the RFID tag.
The RFID tag may recognize a command defined by the RFID reading apparatus and parameters relevant to the command, and transmit data stored in the RFID tag or information related to a status of the RFID tag to an RFID tag reader as a tag response. In this case, since the power available for a digital circuit is limited, distance of data communication may be normally no more than 10 m. Furthermore, a conventional RFID system is typically for reading an identification code of a small size stored in a memory of the RFID tag.